Abstract:

A bearing arrangement is provided that reduces effects of differences in
rates of thermal expansion between transmission housings and shaft
assemblies that are made from different materials. The bearing
arrangement locates the bearings with respect to other components of a
shaft assembly in a manner that establishes a bearing setting stack path
along components that are made from materials having common coefficients
of thermal expansion, despite the shaft assembly and bearing arrangements
being mounted within a housing that is made from a material which has a
dissimilar coefficient of thermal expansion.

Claims:

1. A heavy duty transmission, comprising:a housing made from a first
material having a first coefficient of thermal expansion;a clutch
assembly provided within the housing;a rotating shaft in driving
communication with the clutch assembly and being made from a second
material having a second coefficient of thermal expansion that is less
than the first coefficient of thermal expansion such that for a given
increase in temperature, the housing undergoes a greater amount of
thermal expansion than does the rotating shaft;a bearing arrangement
supporting the rotating shaft within the housing and including,an end
bearing being concentrically seated upon and axially fixed to an end of
the rotating shaft;an intermediate bearing being coaxially aligned with
the end bearing and concentrically spaced from the rotating shaft; anda
bearing retainer that has a counterbore which concentrically houses at
least part of the end bearing therein, and a lip that is sandwiched
between the end and intermediate bearings.

2. The heavy duty transmission of claim 1, the bearing arrangement further
comprising a clutch bearing that is mounted axially spaced from the end
and intermediate bearings and concentrically seated upon and axially
fixed to the rotating shaft.

3. The heavy duty transmission of claim 2, the bearing arrangement further
comprising a retainer nut that is attached to the rotating shaft and
abuts the end bearing so as to prevent axial movement of the end bearing
with respect to the rotating shaft in a first direction.

4. The heavy duty transmission of claim 3, the rotating shaft further
comprising a shoulder that abuts the clutch bearing so as to prevent
axial movement of the clutch bearing with respect to the rotating shaft
in a second, opposite direction.

5. The heavy duty transmission of claim 4, the bearing arrangement further
comprising at least one shim that is sandwiched between the clutch
bearing and the shoulder of the rotating shaft.

6. The heavy duty transmission of claim 4, further comprising a gear that
is mounted concentrically outside of the rotating shaft between the
intermediate and clutch bearings.

7. The heavy duty transmission of claim 6, the gear further comprising a
reduced diameter segment at an end thereof, and wherein an inner race of
the intermediate bearing is seated upon the reduced diameter segment of
the gear.

8. A heavy duty transmission, comprising:a housing made from a first
material having a first coefficient of thermal expansion;a rotating shaft
in driving communication with the clutch assembly and being made from a
second material having a second coefficient of thermal expansion that is
less than the first coefficient of thermal expansion such that for a
given increase in temperature, the housing undergoes a greater amount of
thermal expansion than does the rotating shaft;a bearing retainer mounted
concentrically outside of the rotating shaft, the bearing retainer
including,a cylindrical sidewall;a flange extending radially outwardly
from the cylindrical sidewall; anda lip extending radially inwardly from
the cylindrical sidewall; anda pair of bearings abutting a pair of
opposing surfaces of the lip of the bearing retainer.

9. The heavy duty transmission of claim 8, further comprising a least one
shim that is sandwiched between at least one bearing of the pair of
bearings and the lip of the bearing retainer.

10. The heavy duty transmission of claim 9, the bearing retainer further
comprising an annular land that is recessed into an end thereof, the at
least one shim being seated against the annular land of the bearing
retainer.

11. The heavy duty transmission of claim 8, wherein the flange of the
bearing retainer is connected to the housing of the transmission.

12. The heavy duty transmission of claim 11, wherein the flange of the
bearing retainer is mounted to an outer surface of the housing of the
transmission.

13. The heavy duty transmission of claim 8, wherein the pair of bearings
have different outer diameters such that the pair of bearings includes a
smaller diameter bearing and a larger diameter bearing.

14. The heavy duty transmission of claim 8, the bearing retainer further
comprising a counterbore that extends axially into the bearing retainer.

15. The heavy duty transmission of claim 14, the bearing retainer further
comprising a counterbore that extends axially into the bearing retainer.

16. The heavy duty transmission of claim 15, wherein the smaller diameter
bearing is seated in the counterbore of the bearing retainer.

17. The heavy duty transmission of claim 13, further comprising a gear
that is mounted concentrically outside of and rotatable with respect to
the rotating shaft.

18. The heavy duty transmission of claim 17, wherein an inner race of the
larger diameter bearing is seated upon an outer surface of the gear.

19. The heavy duty transmission of claim 18, further comprising a clutch
bearing that is mounted radially between the gear and the rotating shaft.

20. The heavy duty transmission of claim 19, further comprising a retainer
nut that is connected to the rotating shaft and restricting axial
movement of the smaller diameter bearing in a first direction; and a
shoulder defined in an outer surface of the rotating shaft and
restricting axial movement of the clutch bearing in a second, opposite
direction.

Description:

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001]This application seeks priority as a continuation-in-part from U.S.
Non-Provisional patent application Ser. No. 11/683,709, filed on Mar. 8,
2007, and also seeks priority under 35 U.S.C. §119(e) to U.S.
Provisional Patent Application Ser. No. 61/108,348, filed on Oct. 24,
2008, the entireties of which are expressly incorporated by reference
herein in their entireties, as if fully set forth herein.

BACKGROUND OF THE INVENTION

[0002]1. Field of the Invention

[0003]The present invention relates generally to transmissions and more
specifically to bearing arrangements of shaft assemblies within marine
transmissions.

[0004]2. Discussion of the Related Art

[0005]It is a common practice to fabricate marine transmission housings
out of aluminum castings to reduce the overall weight of a transmission.
Notwithstanding, it is noted that components of transmission shaft
assemblies such as, for example, clutch shaft assemblies and their
respective bearing arrangements are typically made from steel. However,
aluminum has a different coefficient of thermal expansion than steel,
whereby components made from aluminum tend to expand to a greater extent
than do components made from steel.

[0006]Accordingly, within a transmission, shaft assemblies and their
bearing arrangements that are made from steel expand relatively less than
the aluminum transmission housing components per unit of temperature
increase. Such differing material characteristics can present problems
when, for example, steel bearings of a bearing arrangement that support a
steel shaft assembly are set or seated within opposing aluminum walls of
an aluminum transmission housing. That is because when the transmission
increases temperature, a distance between the opposing aluminum walls
increases to a greater extent than does a length of the steel shaft
assembly and distance between the bearings that support the shaft
assembly, which are set within the aluminum walls.

[0007]Stated another way, a "setting" or clearance value, which is defined
between the aluminum wall and respective bearing, increases with
increases in temperature. Such additional clearance or increase in
bearing setting allows the bearings and the shaft assembly components to
axially float such that the shaft experiences a noticeable increase in
end-play. This can lead to uneven bearing roller loading and uneven
loading of gears that are driven by the shaft assembly, leading to
premature wear of the bearings, gears, and/or other components within the
transmission that require alignment with a centerline of the shaft.

[0008]Numerous attempts have been made to resolve such issues associated
with discrepancies in coefficients of thermal expansion between housings
and bearings. Most of these attempts include complex assemblies that have
thrust washers and/or other components made from polymeric, elastomeric,
or various exotic materials. However, components made from such materials
can be expensive and wear out more quickly than other transmission
components, leading to their own failure or failure of cooperating
components.

SUMMARY OF THE INVENTION

[0009]The present invention provides a bearing arrangement to reduce the
effects of differences in rates of thermal expansion between transmission
housing components and shaft assembly or bearing components. This can be
accomplished by providing a bearing arrangement that locates the bearings
with respect to other components of a shaft assembly in a manner that
establishes a bearing setting stack path along components that are made
from materials having common coefficients of thermal expansion, despite
the shaft assembly and bearing arrangement(s) being mounted within a
housing that is made from a material which has a dissimilar coefficient
of thermal expansion. Correspondingly, the components of the bearing
setting stack path act in a unitary manner in response to changes in
temperature, ensuring that bearings within the bearing arrangements do
not cycle between being tightly set or loosely set. In this regard, the
bearings maintain the shaft in a constant position with respect to the
other components of the shaft assembly which maintains alignment and
registration integrity of the rotating components within the
transmission.

[0010]According to one aspect of the invention, a marine or other heavy
duty transmission is provided that has a housing that is made from a
first material having a first coefficient of thermal expansion and a
clutch assembly provided within the housing. A rotating shaft is in
driving communication with the clutch assembly and is made from a second
material having a second coefficient of thermal expansion that is less
that the first coefficient of thermal expansion. Accordingly, for a given
increase in temperature, the housing undergoes a greater amount of
thermal expansion than does the rotating shaft. A bearing arrangement
supporting the rotating shaft within the housing includes an end bearing
that is concentrically seated upon and axially fixed to an end of the
rotating shaft. An intermediate bearing is coaxially aligned with the end
bearing and concentrically spaced from the rotating shaft. A bearing
retainer is provided that has a counterbore which concentrically houses
at least part of the end bearing therein. The bearing retainer also has a
lip that is sandwiched between the end and intermediate bearings.

[0011]In another aspect of this embodiment, the bearing arrangement
includes a clutch bearing that is mounted axially spaced from the end and
intermediate bearings and is concentrically seated upon and axially fixed
to the rotating shaft. The bearing arrangement can also include a
retainer nut that is attached to the rotating shaft and abuts the end
bearing, preventing axial movement of the end bearing with respect to the
rotating shaft in a first direction. Furthermore, a shoulder can be
provided on the rotating shaft, with the shoulder abutting the clutch
bearing so as to prevent axial movement of the clutch bearing with
respect to the rotating shaft in a second, opposite direction. Shims can
be provided within the bearing arrangement, for example between the
clutch bearing and shoulder of the rotating shaft or between one of the
end and intermediate bearings and the bearing retainer.

[0012]According to another aspect of this embodiment, a gear, for example
a pinion gear, can be mounted concentrically outside of the rotating
shaft and axially between the intermediate and clutch bearings, the gear
driving various components within the clutch assembly. The gear can have
a reduced diameter segment at an end thereof, and an inner race of the
intermediate bearing is seated upon the reduced diameter segment of the
gear.

[0013]According to yet anther preferred embodiment, the bearing retainer
includes a cylindrical sidewall. A flange that extends radially outwardly
from the cylindrical sidewall and a lip extends radially inwardly from
the cylindrical sidewall. A pair of bearings abuts a pair of opposing
surfaces of the lip of the bearing retainer.

[0014]In a further aspect of this embodiment, the bearing retainer has an
annular land that is recessed into an end thereof, and a shim is seated
against the annular land of the bearing retainer and therefore between
the bearing retainer and, for example, the intermediate bearing.

[0015]According to yet another aspect of this embodiment, the flange of
the bearing retainer is connected to the housing of the transmission. The
flange can be mounted to an outer surface or other appropriate surface of
the transmission housing.

[0016]In yet another aspect of this invention, the bearings of the pair of
bearings have different outer diameters such that the pair of bearings
includes a smaller diameter bearing and a larger diameter bearing. The
bearing retainer can further include a counterbore that extends axially
into the bearing retainer and the counterbore can house the smaller
diameter bearing at least partially therein.

[0017]These, and other aspects and objects of the present invention will
be better appreciated and understood when considered in conjunction with
the following description and the accompanying drawings. It should be
understood, however, that the following description, while indicating
preferred embodiments of the present invention, is given by way of
illustration and not of limitation. Many changes and modifications may be
made within the scope of the present invention without departing from the
spirit thereof, and the invention includes all such modifications.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]Preferred exemplary embodiments of the invention are illustrated in
the accompanying drawings in which like reference numerals represent like
parts throughout, and in which:

[0019]FIG. 1 is a cross-sectional view of a clutch shaft assembly of a
prior art marine transmission;

[0020]FIG. 2 is an end view of a marine transmission of a bearing
arrangement in accordance with the present invention;

[0021]FIG. 3 is a cross-sectional view of a marine transmission of a
bearing arrangement in accordance with the present invention;

[0022]FIG. 4 is an enlarged cross-sectional view of a clutch shaft
assembly of a marine transmission having a bearing arrangement in
accordance with the present invention;

[0023]FIG. 5 is an enlarged cross-sectional view of an output shaft
assembly of a marine transmission having a bearing arrangement in
accordance with the present invention;

[0024]FIG. 6 is a cross-sectional view of a marine transmission
incorporating a first variant of the bearing arrangement of FIG. 3;

[0025]FIG. 7 is a cross-sectional view of a marine transmission and
bearing arrangement of FIG. 6, showing a bearing setting stack path;

[0026]FIG. 8 is a cross-sectional view of a marine transmission
incorporating a second variant of the bearing arrangement of FIG. 3;

[0027]FIG. 9 is a cross-sectional view of a marine transmission and
bearing arrangement of FIG. 8, showing a bearing setting stack path;

[0029]FIG. 11 is another pictorial view of the bearing retainer of FIG. 6;
and

[0030]FIG. 12 is a cross-sectional view of the bearing retainer of FIG.
10, taken through line 12-12.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031]With reference to the drawings, and particularly to FIG. 1, there is
shown a cross-sectional view of a prior art clutch shaft assembly 102 of
a marine transmission 100. Components of the clutch shaft assembly 102,
for example, the clutch shaft 110, are made from steel while the
transmission housing 104 is made from aluminum. A length of thermal
expansion of the clutch shaft assembly 102 is defined as a change in a
distance between the ends of the clutch shaft 110 due to a change in
temperature. A length of thermal expansion in the transmission housing
104 is defined as a change in a distance between the end walls of
transmission housing 104, against which the outer races of thrust
bearings 106 and 108 are set, due to a change in temperature. Since
aluminum has a greater coefficient of thermal expansion than steel, the
length of thermal expansion of the transmission housing 104 is greater
than the length of thermal expansion of the clutch shaft assembly 102.

[0032]Still referring to the prior art bearing arrangement of FIG. 1, a
setting stack path is shown by the series of arrows that define a closed
path. It is noted that the setting stack path illustrates that the
bearing arrangement is axially restrained at its ends by the transmission
housing 104. Since the aluminum transmission housing 104 has a greater
length of thermal expansion than the clutch shaft assembly 102,
increasing temperatures of the transmission 100 cause increasing setting
of the thrust bearings 106 and 108, creating larger clearances between
the thrust bearings 106, 108 and the transmission housing 104. This can
lead to misalignment of components and/or damage to components in the
transmission 100.

[0033]FIG. 2 shows an end view of a marine transmission 10 that includes
an aluminum housing 20. A cutting plane line 12 is drawn through a
centerline of a primary clutch shaft assembly 14 and an output shaft
assembly 16. The marine transmission 10 also includes a secondary clutch
shaft assembly 18 and a transmission housing 20. FIGS. 3-9 show various
bearing arrangements 1 of the invention. The bearing arrangements 1 are
used to locate rotating components within the transmission 10 and
maintain their respective positions during use. This is done by
purposefully designing the bearing setting stack, such bearing setting
stack being the axially abutting components that, in combination, set the
bearing and therefor locate or restrict axial movement thereof so that
the entire bearing setting stack reacts, in a thermal expansion sense, as
a unit, instead of different portions of the bearing setting stack
reacting with different rates of thermal expansion to changes in
temperature.

[0034]For example, the bearing arrangements 1 are provided in bearing
setting stacks that are assembled from components which are made from
materials having analogous coefficients of thermal expansion. This allows
clearances between components of the stack to remain generally constant
during use so that the stack does not unduly loosen or tighten when
exposed to variations in temperature. Preferably, the bearing
arrangements 1 are configured so that both ends of the bearing setting
stack are axially anchored, directly or indirectly, to a common component
such as a rotating shaft that defines a central axis of the shaft
assembly.

[0035]Referring now to FIGS. 3-4, a bearing arrangement 1 includes a
pinion gear thrust (or intermediate) bearing 22, a pinion gear roller
bearing 49, a clutch shaft thrust (or end) bearing 24, a shaft roller
bearing 26 and a thrust washer 30. A primary clutch shaft assembly 14 is
rotatably supported by the bearing arrangement 1 and includes a clutch
shaft 32, a pinion gear 34, a retainer nut 55, a pinion retainer 28, and
a clutch assembly 36. An inner race 38 of the clutch shaft thrust (end)
bearing 24 is retained on one end of the clutch shaft 32 and the other
end by retainer nut 55 and an inner race 40 of the shaft roller bearing
26 is retained on the other end of the clutch shaft 32. An outer race 42
of the clutch shaft thrust (end) bearing 24 is retained at one end by an
end cap or collector near a first end of the transmission housing 20 and
an outer race 44 of the shaft roller bearing 26 is retained in the other
end of the transmission housing 20. The pinion gear 34 rotates in either
direction relative to the clutch shaft 32, depending on clutch
engagement. An inner race 46 of the pinion gear thrust (intermediate)
bearing 22 is retained on one end of the pinion gear 34 with a pinion
bearing retainer 28. An outer race 48 of the pinion gear thrust
(intermediate) bearing 22 is retained in the transmission housing 20. The
pinion bearing retainer 28 is preferably attached to the one end of the
pinion gear 34 with fasteners (not shown) or the like. A pinion gear
roller bearing (or clutch) bearing 49 is retained in a pinion bore 51
disposed in substantially the other end of the pinion gear 34, such that
the pinion gear 34 rotates relative to the clutch shaft 32.

[0036]The thrust washer 30 is retained on the pinion bearing retainer 28
with at least two dowels 50 or the like. The inner race 38 of the clutch
shaft thrust (end) bearing 24 physically contacts the thrust washer 30
and frequently rotates in a direction opposite thereto. The thrust washer
30 is fabricated from a special material that is resistant to wear, due
to frictional contact from the inner race 38 of the clutch shaft thrust
(end) bearing 24. The special material was not available until recently.
The special material must have a pressure-velocity value of at least
1,000,000 psi-ft/min. A suitable special material is sold under the trade
name of Vespel SP-21. Vespel SP-21 is manufactured by DuPont, Inc.
However, the special material should not be limited to Vespel SP-21, but
should include any material that has pressure-velocity characteristics of
at least 1,000,000 psi-ft/min. Thrust washers fabricated from even the
hardest materials in the past would wear out in a short period of time
and fail. The thrust washer 30 (fabricated from the special material)
allows close placement of the thrust (intermediate and end) bearings 22,
24. The length of thermal expansion is limited to the distance from the
opposite ends of the two thrust (intermediate and end) bearings 22, 24.

[0037]With reference to FIG. 5, the output shaft assembly 16 includes an
output shaft 58 and an output gear 60. The output gear 60 is driven by
the pinion gear 34. Inner races of a first thrust bearing 52 and a second
thrust bearing 54 rotate in the same direction and thus are placed in
contact with each other without inducing wear. The first thrust bearing
52 is retained between a second thrust bearing 54 and a bearing retaining
cap 64. The bearing retaining cap 64 is attached to the transmission
housing 20 with a plurality of fasteners 66.

[0038]The second thrust bearing 54 is retained between the first thrust
bearing 52, a tubular spacer 66, and a second step 68 in the output shaft
58. A shaft roller bearing 56 is retained between a third step 71 in the
output shaft 58 and an output flange 70. The output flange 70 is secured
to an end of the output shaft 58 with an end plate 72 and at least two
fasteners 74. The length of thermal expansion is limited to the distance
from the opposite ends of the first and second thrust bearings.

[0039]Referring now to FIGS. 6-9, in some embodiments, no thrust washer 30
is implemented within the bearing arrangement 1. Such embodiments also
incorporate a tapered roller bearing as (clutch) bearing 49, in lieu of
the cylindrical roller (clutch) bearing 49 seen in FIG. 4. The
embodiments of FIGS. 6-9 include bearing arrangements 1 that are
integrated into a bearing setting stack that is axially anchored on each
end, directly or indirectly, to the clutch shaft 32. As seen best in FIG.
7, a bearings setting stack path is represented by a closed loop series
of arrows that pass through the components of the bearing setting stack,
between the two ends of the bearing arrangement 1.

[0040]Referring specifically to FIGS. 6 and 7, as compared to the
arrangement seen in FIG. 4, each of bearings 22 and 24 is flipped so that
the respective tapering portions face the other way. Accordingly, the
rollers of bearing 22 slant conically inward to the right as illustrated,
or toward bearing 24. The rollers of bearing 24 slant conically inward to
the left as illustrated, or toward bearing 22. The rollers of bearing 49
slant conically inward to the right as illustrated, or toward the bearing
22. Bearing 49 is sandwiched and axially restrained between the pinion
gear 34 on one side and a shim 35 on the other which abuts a shoulder 32A
on the clutch shaft 32.

[0041]Still referring to FIGS. 6 and 7, in this configuration, all of the
bearings 22, 24, and 49 are contained within or axially abut or set
against ferrous components, whereby effects of a greater rate of thermal
expansion of the aluminum housing when compared to a rate of thermal
expansion of the bearings and components of the clutch shaft assembly 14
are mitigated. Stated another way, along the length of the clutch shaft
32, the bearings 22, 24, and 49 are longitudinally confined or restrained
by ferrous components which are preferably all connected to or anchored
by the clutch shaft 32 itself. The ferrous components can include various
ones of, for example, (i) bearing retainer 28, (ii) an endcap that
encapsulates the end-most portion of the clutch shaft assembly 14, (iii)
shoulders, ledges, lips, projections, counterbores, or other suitable
mechanical interfacing-type structures in the bearing retainer 28 and
endcap, shoulders, ledges, lips, projections, upon the bearing retainer
28 and endcap, (iv) shoulders, ledges, lips, projections, counterbores,
or other suitable mechanical interfacing-type structures in the bearing
retainer 28 and endcap, shoulders, ledges, lips, projections on the
clutch shaft 32, pinion gear 34, and/or other ferrous structures that are
suitably close to the clutch shaft assembly 14 to serve as bearing
support-type structures.

[0042]Referring now to FIGS. 6-7 and 10-12, bearing retainer 28 is
preferably implemented as part of the bearings setting stack and serves
as a transitioning medium between the bearing arrangement 1 and clutch
shaft assembly 14, and the aluminum housing 20 of transmission 10.
Bearing retainer 28 has a body with a cylindrical sidewall 130 and
defines a back side 132 that faces away from the clutch assembly 36 and a
front side 134 that faces toward the clutch assembly 36. A counterbore
140 extends into the back side 132 of the body of the bearing retainer
28.

[0043]Still referring to FIGS. 6-7 and 10-12, a flange 145 extends
radially out from an outer surface of the sidewall 130, on the other side
of the sidewall 130 from the counterbore 140. A groove 148 extends into a
forward facing surface of the flange 145, extending entirely about but is
radially spaced from the sidewall 130 and is configured to hold an 0-ring
or other seal that sits between the bearing retainer 28 and the aluminum
housing 20.

[0044]In some embodiments, the flange 145 is configured to cooperate with
the other portions of the bearing retainer 28 in a manner that allows the
bearing retainer 28 to accommodate the differences between the thermal
expansion rates of the aluminum transmission housing 20 and the various
ferrous components of the clutch shaft assembly 14. For example, a
diameter of flange 145 and the radial distance that the flange 145
extends from sidewall 130 is selected along with a thickness dimension of
the flange 145 to provide a desired amount of flexibility or
delectability with respect to the remainder of the bearing retainer 28.

[0045]In such configuration, while the remainder of body of bearing
retainer 28 is anchored between, for example, the bearings 22 and 24, the
flange 145 can bend away from the clutch assembly 36 when it is being
pushed by the aluminum housing 20, to which it is mounted, when the
aluminum housing 20 undergoes a greater amount of thermal expansion than
does the components of the bearing arrangement 1 or bearing setting
stack. The flexibility of flange 145 therefor absorbs and accommodates
such difference in thermal expansion rates in a manner that the greater
amount of thermal expansion of the aluminum housing 20 is not translated
to the bearing setting stack, whereby the bearing settings are not
increased and the bearing setting stack is not loosened.

[0046]Referring yet further to FIGS. 6-7 and 10-12, a lip 150 extends
radially inward from an inner surface of the sidewall 130 of bearing
retainer 28. The lip 150 is axially spaced from the front side 134 of the
body of the bearing retainer 28 such that a first annular land 155 is
defined by the forward facing surface of the lip 150. A second annular
land 158 is defined on an opposing side of the lip 150; in other words,
facing toward the back side 132 of the body of bearing retainer 28.

[0047]As seen in FIG. 7, a shim 160 can be seated against the first
annular land 158. Shim 160 fits between respective portions of the
bearing retainer 28 and bearing 24, while noting that the outer surface
of front side 155 abuts a side surface of outer race 48. Also seen in
FIG. 7, the bearing 24 is seated against the second annular land 158 of
lip 150, namely, a side surface of the outer race 42 abuts the second
annular land 158, whereby the lip 150 of bearing retainer 28 is
incorporated into the bearing setting stack.

[0048]Still referring to FIG. 7, the bearing setting stack is defined by
the components that axially abut each other and correspondingly locate
the bearings of the bearing assembly 1. Such components of the bearing
setting stack include, (i) bearing 49 and its respective rollers and
raceways and, optionally, its shims 35, (ii) clutch shaft 32, (iii) a
retainer nut 55, (iv) bearing 24 and its respective rollers and raceways
38, 42, (v) lip 150 and/or other portions of bearing retainer 28 and,
optionally, its shims 160, (vi) bearing 22 and its respective rollers and
raceways 48, 46, and (vii) pinion gear 34. Once again, in preferred
embodiments, all or substantially all of these components within the
bearing setting stack are made from a ferrous material, most preferably
steel.

[0049]Referring now to FIGS. 8 and 9, some alternative embodiments are
contemplated in which no bearing retainer 28 is utilized in the bearing
arrangement 1, but instead the bearings 22 and 24 directly abut each
other or optionally abut each other with a shim therebetween. FIG. 8
shows the bearings 22 and 24 with their rollers tapering inwardly towards
each other, similar to the arrangement seen in FIG. 4. FIG. 9 shows the
bearings 22 and 24 with their rollers tapering the opposite direction,
that is, inwardly toward each other.

[0050]Referring now specifically to FIG. 9, another bearing setting stack
path is shown, having bearings 22 and 24 in an adjacent face to face
relationship with each other without an intervening lip of bearing
retainer 28. Accordingly the bearing setting stack path seen in FIG. 9 is
largely analogous to that in FIG. 7, only being devoid of the lip 150 of
bearing retainer 28.

[0051]The bearing arrangement 1 need not be limited to clutch shafts for
marine transmissions, but can include any shaft application with an
object that rotates on the shaft in a direction opposite of the shaft.
The object could be a gear, a clutch, a clutch assembly or any other
device. Regardless, it is noted that many changes and modifications may
be made to the present invention without departing from the spirit
thereof. The scope of some of these changes is discussed above. The scope
of others will become apparent from the appended claims.